LAS VEGAS--The Consumer Electronics Show is the big coming-out party for the U.S. launch of Nokia's new Windows Phone smartphones.

On the CES stage Monday afternoon here, Nokia CEO Stephen Elop said the handset maker will start selling the Lumia 710, which Nokia introduced in December, with T-Mobile USA on Wednesday. He and others spent the remainder of the press event focusing on the unveiling of the Lumia 900 for AT&T's network.

The 900, the first LTE 4G device running the Windows Phone OS, is designed for people who want a rich-media experience. Equipped with a Carl Zeiss lens, long-lasting battery life, and a high-end 4.3-inch screen, the phone, which comes in black and blue, includes built-in Facebook chat and Nokia Drive. Along with videoconferencing technology, it has some new social and media features, including hubs that take advantage of partnerships with content makers like ESPN, CNN, Univision, and Sesame Street.

Nokia did not disclose the device's pricing or debut timing, nor did it announce any other devices or carrier partnerships.

Microsoft CEO Steve Ballmer joined Elop on stage briefly to praise the device and set expectations high for increasing Windows Phone sales for AT&T. And Ralph de la Vega, head of wireless for AT&T, predicted that with the Lumia 900, "Nokia will be back in the U.S. in a very big way."

Without mentioning Android, Elop made subtle jabs at the Google mobile operating system by emphasizing a consistent user experience across Windows Phone 7 devices, even if they come from different manufacturers. He avoided answering a question regarding the possibility of an upcoming Nokia tablet running the Microsoft OS.

Nokia announced its partnership with Microsoft early in 2011, making Microsoft's Windows Phone platform its exclusive smartphone operating system. Since then, the company has been working hard to get new smartphones on the market. For several years, Nokia has been nearly nonexistent in the U.S. market. And the company hopes that its new Windows Phone products will get it back in the game. But it faces stiff competition from dozens of Google Android devices and Apple's iPhone.

The success of the Nokia Windows Phones in the United States is crucial, as the company attempts to make itself a relevant player in the U.S. smartphone market.

About the author

Marguerite Reardon has been a CNET News reporter since 2004, covering cell phone services, broadband, citywide Wi-Fi, the Net neutrality debate, as well as the ongoing consolidation of the phone companies. E-mail Maggie.
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